This invention relates to an electronic musical instrument which has a memory for storing a series of tone data, and which functions to optionally correct and delete the tone data stored in the memory or to insert a prescribed tone data into the memory.
In recent years, an electronic musical instrument has been made commercially available which is capable of storing in its memory musical tone data preselected by a user and, in performance, allowing the tone data to be read out in turn from the memory through operating a one-key play key or auto-play key to allow the tone generation in turn, thus allowing an automatic performance of the music.
This type of electronic musical instrument has a display means at a position close to, for example, its keyboard, on which is displayed the number of steps increasing each time the user inserts the tone data into the memory. Through reading a note or notes by the user from his score and actuating in turn the key corresponding to that note or notes at a prescribed timing and interval, the corresponding tone data is written into the memory. Assume that, at this time, a misreading by the user of the note frequency occurs, which causes the writing of erroneous tone data into the memory. In such a case, the step number is returned or reset to "0" and the memory address is thereby reset to the foremost address. Subsequently, while viewing the display of the step number, the memory address is forwardly stepped-up to an address corresponding to the erroneously input memory position to correct the memory content at that address. Where the missed tone data is inserted, the correct tone data already written is once deleted and thereafter the deleted tone information is inserted into a memory position immediately succeeding the missed memory position. Thus, there is a shortage of one memory position. That is, the correct tone data already input into the memory positions of the addresses succeeding to the address corresponding to said missed memory position have to be totally deleted and input once again. More specifically, while deleting the memory contents by depressing the delete key, the address position is returned to the address corresponding to the missed memory position and thereafter the correct tone information is input into the succeeding memory positions.
In any of the above-mentioned methods, however, it is uncertain or unclear whether or not the step number displayed as a result of restoring the address position corresponds to the note erroneously inputted, with a result that difficulties are encountered in performing the operation of correctly restoring the address position. Further, in the case of inputting the missed tone data, even the previous tone data correctly input is deleted, with the result that the time and labour necessary for the inputting operation are duplicated.
Further, where the delete key is used, it is considered useful to inform the operator of a completion of the deletion of tone data by means of a buzzer. In this prior art, however, the contents of the tone data as deleted fail to be confirmed, particularly when the delete key, is depressed several times consecutively. Such the inconveniences involved in the prior art.